Mechanical arrangement for trimming an outboard motor

ABSTRACT

Disclosed herein is a marine propulsion device including means connecting a swivel bracket and a transom bracket to provide for vertical swinging movement therebetween about a horizontal axis and to permit displacement of the horizontal axis in the fore and aft direction relative to the transom bracket, together with means for adjustably displacing the horizontal axis in the fore and aft direction, whereby to control the trim of the propulsion unit relative to the supporting boat.

United States Patent Blanchard 1 Sept. 5, 1972 [54] MECHANICAL ARRANGEMENT FOR 3,511,460 5/ 1970 Shimanckas ..1 15/ 17 X TRIMMING AN OUTBOARD MOTOR 3,240,452 3/1966 Cheeseboro ..115/41 HT X [72] Inventor: Clarence E. Blanchard I Phoenix, 3,473,325 10/1969 Vargo ..1 15/17 X A z Primary ExaminerMilton Buchler Asslgnee: outboard Mamie Corporatllm, Assistant ExaminerCarl A. Rutledge wallkegan, Attorney-Wheeler, Wheeler, House & Clemency and 221 Filed: Sept. 25, 1970 Robert Gerlmg pp 75,579 57 ABSTRACT Disclosed herein is a marine propulsion device includ- [52] US. Cl. ..ll5/4l HT, 248/4 ing means connecting a Swivel bracket and a transom [51] Int. Cl. ..B63h 5/12 bracket to provide for vertical Swinging movement [58] F'eld 41 1&248/4 therebetween about a horizontal axis and to permit displacement of the horizontal axis in the fore and aft [56] References C'ted direction relative to the transom bracket, together UNITED STATES PATENTS with means for adjustably displacing the horizontal axis in the fore and aft direction, whereby to control lg; 2 E2 the trim of the propulsion unit relative to the supporte as er b L 3,333,798 8/1967 Stroud ..24s/4 mg 0a 2,961,207 11/1960 Irgens ..1 15/41 R X 9 Claims, 3 Drawing Figures MECHANICAL ARRANGEMENT FOR TRIMMING AN OUTBOARD MOTOR BACKGROUND OF THE INVENTION Marine propulsion units have included, for many year, thrust pins which transmitted propulsive thrust from the propulsion unit to the boat and which were selectively mounted in the clamp or transom bracket and engaged by the swivel bracket to permit adjustment of the trim of an outboard motor or stem drive unit so that the propeller shaft could be located in a generally horizontal position for optimum performance.

While such arrangements did provide some general degree of trim adjustment, i.e., adjustment of the propulsion unit so that the propeller shaft was horizon tal, such prior arrangements were capable only of course adjustment, and there was, until recently, no arrangement available for fine trimming, and in particular, for trimming under way, so as to take into account changes in trim occurring by reason of the changes in the attitude of the boat such as can occur in response to wind conditions and shifting of the occupants in the boat. In addition, changes in the direction of travel of the boat can effect trim because of the change in relation to the wind and because of water surface conditions.

One device recently introduced on the market provided for trim adjustment under way by means of a hydraulic device which eliminated the previous thrust pin and which was operable to selectively tilt the propulsion unit about the tilt pin axis. This device was and is undesirable from the standpoint that the thrust to be transmitted from the propulsion unit to the boat was necessarily transmitted through the hydraulic device.

SUMMARY OF THE INVENTION The invention provides an arrangement in a marine propulsion device for adjustably shifting in the fore and aft direction the horizontal tilt axis between the transom bracket and the swivel bracket so as to afford adjustment of the trim of the marine propulsion device even when under way and while maintaining thrust transmission from the propulsion unit to the supporting boat through the so-called thrust pin or other arrangement independent of the trimming arrangement.

In this regard, in one embodiment of the invention, the swivel bracket journals a tilt pin having spaced bearing portions received in slots formed in the transom bracket and elongated in the fore and aft direction so as to afford both rotary movement of the tilt pin and displacement of the tilt pin in the fore and aft direction within the slots. In order to cause displacement of the tilt pin in the fore and aft direction, in one embodiment, the tilt pin includes spaced pinion portions and the transom bracket is provided with spaced racks which extend in the fore and aft direction adjacent to the slots and which are respectively in mesh with the pinion portions of the tilt pin. In addition, means, which can be in the form of a lever, is provided for rotating the tilt pin so as to effect forward and rearward tilt pin movement in response to such rotary movement and as a consequence of the meshed engagement of thetilt pin pinion portions with the spaced racks.

In another embodiment of the invention, the well known thrust pin is omitted and there is provided a thrust transmitting and trimming connection extending between the lower end of the propulsion unit and a mechanism mounted adjacent to the bottom of the transom. Such means comprises an element which can be threaded in and out of a support and which engages the lower end of the propulsion unit to tilt the propulsion unit about the horizontal tilt axis, thereby providing a trim adjustment which can be relatively finely controlled but which cannot readily be adjusted under way. In addition, the arrangement includes means for displacing the horizontal tilt axis fore and aft to provide fine trim adjustment under way so as to compensate for varying conditions.

One of the principal objects of the invention is the provision of an arrangement for affording adjustment of the trim of a marine propulsion device while maintaining thrust transmission from the propulsion unit to the supporting boat through the so-called thrust pin or other thrust transmitting arrangement.

Another object of the inventionis to provide an arrangement for affording fine trim adjustment in addition to the prior conventional course adjustments made by selectively locating the thrust pin in relation to the transom bracket.

Another of the principal objects of the invention is the provision of an arrangement for shifting, in a fore and aft direction, the tilt pin connecting the swivel bracket to the transom bracket of a marine propulsion device, whereby to pivot the propulsion unit about the thrust pin or other thrust transmitting and trim controlling arrangement so as to afford additional trim adjustment capability.

Still another object of the invention is the provision of a relatively simple and effective arrangement affording fine adjustment to the trim of a marine propulsion device, which arrangement can be readily and economically manufactured and will provide reliable service over a long and useful life.

Other objects and advantages of the invention will become known by reference to the following description and accompanying drawings.

DRAWINGS FIG. I is a side elevational view of one embodiment of an outboard motor in accordance with the invention.

FIG. 2 is an exploded perspective view of various of the components included in the outboard motor shown in FIG. 1.

FIG. 3 is a side elevational view of another outboard motor embodying various of the features of the invention.

GENERAL DESCRIPTION Shown in FIG. 1 of the drawings is a marine propulsion device in the form of an outboard motor 11 which embodies various of the features of the invention. As shown, the outboard motor 11 includes a clamp or other style transom bracket 13 which can be as disclosed, for instance, in the Conover U.S. Pat. No. 3,061,250 and which is adapted to be fixedly attached to the transom 17 of a boat. Attached to the transom bracket 13 for vertical swinging movement about a horizontal tilt axis 19 is a swivel bracket 21 which, in

turn, supports a propulsion unit 23 for steering movement about an axis 27 extending traversely to the horizontal tilt axis 19. The propulsion unit 23 includes a drive shaft 29 which is connected through gearing 31 with a propeller shaft 33 carrying a propeller 37. In order to achieve optimum speed conditions it is desirable to trim the propeller shaft 33 so as to be located as close as possible to the horizontal.

The clamp or transom bracket 13 includes means for affording thrust transmission from the propulsion unit 23 to the boat and for providing a course trim adjustment so as to locate the propeller shaft 33 approximately horizontal. In the disclosed construction, such means includes a series of arcuately arranged holes 39 (which are identified by numeral 34 in FIG. 3 of the Conover US. Pat. No. 3,061,250) and which selectively receive a thrust pin 41 (which is identified by the numeral 33 in FIG. 3 of the Conover US. Pat. No. 3,061,250). The thrust pin 41 is engageable by the swivel bracket 21 to trim the propulsion unit 23 by affording variation in the relationship of the swivel bracket 21 and connected propulsion unit 23 relative to the transom bracket 13 at relatively coarse intervals which, in commercial outboard motors, have been about 3 or 4. Engagement of the swivel bracket 21 against the thrust pin 41 in the clamp bracket 13 also provided the main path for transmission of thrust from the propulsion unit 23 to the boat hull. As thus far described, the construction is entirely conventional and well known.

In accordance with the invention there is provided means which connects the swivel bracket 21 to the clamp bracket 13 so that, in addition to providing vertical tilting of the swivel bracket 21 and connected propulsion unit 23 relative to the clamp bracket 13, there is also permitted displacement of the horizontal tilt axis 19 in the fore and aft direction relative to one of the swivel bracket 23 and transom bracket 13,

together with means for adjustably displacing the horizontal tilt axis 19 in the fore and aft direction.

Such shifting of the horizontal tilt axis in the fore and aft direction causes pivotal movement of the swivel bracket 21 and connected propulsion unit 23 about the thrust pin 41 so as to provide a fine trim adjustment, whereby the propeller shaft 33 can be located for optimum performance, notwithstanding wind and other changes in conditions. In contrast to the impossibility of relocating the thrust pin 41 to change trim during underway conditions, the disclosed arrangement facilitates fine trim adjustments even when under way.

While various arrangements can be employed in accordance with the invention, in the construction disclosed in FIGS. 1 and 2, the means for connecting the swivel bracket 21 to the transom bracket 13 includes a tilt pin 51 which is joumalled in the swivel bracket 21, which can be assembled from two or moreparts as shown, and which has transversely horizontally spaced bearing portions 53 received in transversely horizontally spaced slots 57 which are provided in the clamp or transom bracket 13 and which are elongated in the fore and aft direction. Accordingly, the swivel bracket 21 can rotate in a vertical plane relative to the horizontal tilt pin 51 to afford tilting movement of the propulsion unit 23 and, in addition, the tilt pin 51 is capable of axial rotation, as well ashorizontal displacement in the slots.

While various other arrangements can be employed, in the disclosed construction shown in FIGS. 1 and 2, the means for adjustably displacing the horizontal axis 19 in the fore and aft direction includes transversely horizontally spaced pinion portions 59 on the tilt pin 51 which are in mesh with transversely horizontally spaced racks 61 extending adjacent to the slots 57 in the fore and aft direction on the transom bracket 13, together with means for rotating thetilt pin 51 to thereby selectively horizontally displace the horizontal tilt pin 51 in the slots 57 in the fore and aft direction.

While other arrangements can be employed, such as for instance, an electric motor, in the construction disclosed in FIGS. 1 and 2, the means for rotating the tilt pin 51 comprises an operating lever 62 which is fixed to the tilt pin 51 for common movement therewith and which can be rocked by a hydraulic ram 63 shown in FIG. 1 and remotely controlled from the operators position. Alternatively, the lever can be operated by a linear electric motor or by a remote control connected to the lever 62 by a push-pull linkage or by a bell-crank and rod linkage. In any event, the controlling mechanism desirably includes means for preventing unwanted rotation of the tilt pin so as to assure maintenance of whatever trim condition has been set by the operator.

Shown in FIG. 3 is another embodiment of the invention including an alternate arrangement for transmitting thrust to the boat and for providing a basic trim adjustment. In addition, the arrangement also includes means adjustably displacing the horizontal tilt axis 19 so as to provide fine trim adjustment under way. (Like numerals are applied to the components of the FIG. 3 construction which are similar to the components of the FIG. 1 construction.) As shown in FIG. 3, the alternate thrust transmitting and trimming arrangement includes a support or member 71 which is connected to the boat transom 19 beneath the clamp bracket 13 and cooperating abutment means extending from the member 71 and on the propulsion unit 23. While various arrangements can be employed, in the disclosed construction, the member 71 supports a threaded element or screw 73, which screw can be rotated in the member 71 so as to vary the extent of the screw rearwardly of the boat transom 17. Preferably, thescrew has a conical end 77 which is received in a conical socket 79 on the forward portion of the drive shaft housing 81 or lower end of the propulsion unit 23.

In other respects, the embodiment shown in FIG. 3 is generally similar to the embodiment shown in FIGS. 1 and 2, except that the thrust pin 41 is omitted.

The disclosed construction provides means whereby a fine trim adjustment can be made to a propulsion unit under way so as to locate the propeller shaft in an optimum position for providing optimum speed, which position is generally considered to be horizontal. The disclosed arrangement affords such adjustment while under way by operating the adjustment lever 61 to horizontally shift the tilt pin and thereby alter the trim of the propulsion unit.

While various features of the invention have been disclosed in connection with outboard motors, the principles of the invention are equally applicable to stem drive units.

Various of the features of the invention are set forth in the following claims.

' What is claimed is:

l. A marine propulsion device comprising a first bracket adapted to be fixedly attached to a transom of a boat, a second bracket adapted to support a propulsion unit, means connecting said second bracket to said first bracket for vertical swinging movement of said second bracket relative to said first bracket about a horizontal axis and for displacement of said horizontal axis relative to one of said first and second brackets in the fore and aft direction, and means for adjustably displacing said horizontal axis in the fore and aft direction, whereby to control the trim of the propulsion unit relative to the supporting boat.

2. A marine propulsion device in accordance with claim 1 wherein said means connecting said first bracket to said second bracket comprises a tilt pin rotatably mounted in one of said first and second brackets and including spaced bearing portions, and spaced slots elongated in the fore and aft direction in the other of said first and second brackets and receiving said bearing portions of said tilt pin to afford therein rotary movement of said tilt pin and horizontal displacement of said tilt pin.

3. A marine propulsion device in accordance with claim 2 wherein said means for adjustably displacing said horizontal tilt axis includes spaced pinion portions on said tilt pin, spaced rack portions extending in the fore and aft direction on said other of said first and second brackets and in mesh with said tilt pin pinion portions, and means for rotating said tilt pin to thereby selectively horizontally displace said horizontal tilt pin in said slots in the fore and aft direction.

4. A marine propulsion device in accordance with claim 1 wherein said means for adjustably displacing said horizontal axis in the fore and aft direction includes engageable means on said second bracket and said first bracket for transmitting propulsive thrust from said second bracket to said first bracket.

5. A marine propulsion device in accordance with claim 1 wherein said device includes a propulsion unit connected to said second bracket for steering move ment about an axis transverse to said horizontal axis and wherein said means for adjustably displacing said horizontal axis in the fore and aft direction includes a member adapted to be fixed to the boat transom and engageable means on said member and on said propulsion unit for transmitting propulsive thrust from said propulsion unit to the boat.

6. A marine propulsion device in accordance with claim 5 wherein said member includes means for adjusting the rearward extent of said engageable means on said member.

7. A marine propulsion device comprising a first bracket adapted to be fixedly attached to a transom of a boat, a swivel bracket, means connecting said swivel bracket to said first bracket for vertical swinging movement of said swivel bracket relative to said first bracket about a horizontal axis and for displacement of said horizontal axis relative to oneof said swivel bracket and said first bracket in the fore and aft direction, a propulsion unit connected to said swivel bracket for steering movement about an axis transverse to said horizontal axis, engageable means on said swivel bracket and said first bracket for transmitting propulsive thrust from said propulsion unit to said first bracket, and means for adjustably displacing said horizontal axis in t e fore and tdirec,tion whereby to control the trim 0 said propu sion unit re ative to the supporting boat.

8. A marine propulsion device in accordance with claim 7 wherein said means connecting said first bracket to said swivel bracket comprises a tilt pin rotatably mounted in one of said swivel bracket and said first bracket and including transversely horizontally spaced bearing portions, and transversely horizontally spaced slots elongated in the fore and aft direction in the other of said swivel bracket and said first bracket and receiving said bearing portions of said tilt pin to afford therein rotary movement of said tilt pin and horizontal displacement of said tilt pin, and wherein said means for adjustably displacing said horizontal tilt axis includes transversely horizontally spaced pinion portions on said tilt pin, transversely horizontally spaced rack portions extending in the fore and aft direction on said other of said swivel bracket and said first bracket and in mesh with said tilt pin pinion portions, and means for rotating said tilt pin to thereby selectively horizontally displace said horizontal tilt pin in said slots in the fore and aft direction.

9. A marine propulsion device in accordance with claim 8 wherein said means for rotating said tilt pin comprises a control lever rigidly fixed to said tilt pin. 

1. A marine propulsion device comprising a first bracket adapted to be fixedly attached to a transom of a boat, a second bracket adapted to support a propulsion unit, means connecting said second bracket to said first bracket for vertical swinging movement of said second bracket relative to said first bracket about a horizontal axis and for displacement of said horizontal axis relative to one of said first and second brackets in the fore and aft direction, and means for adjustably displacing said horizontal axis in the fore and aft direction, whereby to control the trim of the propulsion unit relative to the supporting boat.
 2. A marine propulsion device in accordance with claim 1 wherein said means connecting said first bracket to said second bracket comprises a tilt pin rotatably mounted in one of said first and second brackets and including spaced bearing portions, and spaced slots elongated in the fore and aft direction in the other of said first and second brackets and receiving said bearing portions of said tilt pin to afford therein rotary movement of said tilt pin and horizontal displacement of said tilt pin.
 3. A marine propulsion device in accordance with claim 2 wherein said means for adjustably displacing said horizontal tilt axis includes spaced pinion portions on said tilt pin, spaced rack portions extending in the fore and aft direction on said other of said first and second brackets and in mesh with said tilt pin pinion portions, and means for rotating said tilt pin to thereby selectively horizontally displace said horizontal tilt pin in said slots in the fore and aft direction.
 4. A marine propulsion device in accordance with claim 1 wherein said means for adjustably displacing said horizontal axis in the fore and aft direction Includes engageable means on said second bracket and said first bracket for transmitting propulsive thrust from said second bracket to said first bracket.
 5. A marine propulsion device in accordance with claim 1 wherein said device includes a propulsion unit connected to said second bracket for steering movement about an axis transverse to said horizontal axis and wherein said means for adjustably displacing said horizontal axis in the fore and aft direction includes a member adapted to be fixed to the boat transom and engageable means on said member and on said propulsion unit for transmitting propulsive thrust from said propulsion unit to the boat.
 6. A marine propulsion device in accordance with claim 5 wherein said member includes means for adjusting the rearward extent of said engageable means on said member.
 7. A marine propulsion device comprising a first bracket adapted to be fixedly attached to a transom of a boat, a swivel bracket, means connecting said swivel bracket to said first bracket for vertical swinging movement of said swivel bracket relative to said first bracket about a horizontal axis and for displacement of said horizontal axis relative to one of said swivel bracket and said first bracket in the fore and aft direction, a propulsion unit connected to said swivel bracket for steering movement about an axis transverse to said horizontal axis, engageable means on said swivel bracket and said first bracket for transmitting propulsive thrust from said propulsion unit to said first bracket, and means for adjustably displacing said horizontal axis in the fore and aft direction, whereby to control the trim of said propulsion unit relative to the supporting boat.
 8. A marine propulsion device in accordance with claim 7 wherein said means connecting said first bracket to said swivel bracket comprises a tilt pin rotatably mounted in one of said swivel bracket and said first bracket and including transversely horizontally spaced bearing portions, and transversely horizontally spaced slots elongated in the fore and aft direction in the other of said swivel bracket and said first bracket and receiving said bearing portions of said tilt pin to afford therein rotary movement of said tilt pin and horizontal displacement of said tilt pin, and wherein said means for adjustably displacing said horizontal tilt axis includes transversely horizontally spaced pinion portions on said tilt pin, transversely horizontally spaced rack portions extending in the fore and aft direction on said other of said swivel bracket and said first bracket and in mesh with said tilt pin pinion portions, and means for rotating said tilt pin to thereby selectively horizontally displace said horizontal tilt pin in said slots in the fore and aft direction.
 9. A marine propulsion device in accordance with claim 8 wherein said means for rotating said tilt pin comprises a control lever rigidly fixed to said tilt pin. 